by Doc Nickel
Note: This was posted before the Evolution I or II were release so they are not included.
Original Viewloader: 3" PVC elbow with a nipple glued to it. Painted black with a clear plastic cover at one end (hence the "view" loader) and a port like a stock-class tube one-way gate on the other end. Loaded using 10-round tubes.
Later "production" Viewloaders: Injection-molded plastic instead of the PVC. Possibly polystyrene.
First VL-90s (before they were really called that): Blow-molded one piece plastic bodies, with twist-lock caps. One end was a widemouth clear plastic lid, the other was a "cup" to add internal volume. The latch of the clear lids tended to break off (same plastic as model car stuff) and the whole thing still had the same general "plumbing elbow" shape.
First-generation VL-200: Same general shape of the 90, and using the same end caps and cups, but much fatter, nearly 2" larger in diameter.
First-generation VL-2000: Using the 200 body, the first agitated loader (well, production anyway) had the servo and a cheezy battery clip literally hung out in the breeze on the back of the loader body. No cover, fully exposed. For a short while, the 2000 body started having "mounting lugs" molded right into the body to hold the servo. This was just a stopgap until...
The "true" VL-2000: First of the "new generation" loaders; shells molded in halves, new much larger lid for easier loading, snap-type lid molded from a polyurethane to stop cracking problems, and molded with a "case" to enclose the eyes, servo and battery.
At the same time, they released the VL-200: the updated 2K case and lid, but without the motor or compartment.
Later, the VL-2000 was upgraded to use two batteries in series, to give 18V to the servo (which was technically a 12V servo, as I recall). This they called the "Shredder". The extra battery was hung on the outside in a molded case that fit in place of the original battery cover. For short durations it was okay, but the additional voltage burned up a lot of servos and gearboxes.
And about this time, VL released the "stretched" 2K body, called the VL3000. Used the 18V "Shredder" guts, and held a nominal 300 balls.
About '97 or so, they revamped everything into the Revolution. Same style of lid and shell halves, it now incorporated a battery case large enough for both 9Vs inside the body, and included a voltage regulator system to take the 18V and feed the required 12V to the servo. They also added a little bar to "guard" the power switch (having the loader turn itself on in the gearbag happened to everyone at least once) and a low-battery light.
Before too long, the near-$60 pricetag gained a few complaints, so they simplified the controller, ditched one battery and the voltage regulator/power indicator, and brought out the 9V Revolution at about $20 less.
By '99 or so, VL brought out the clear or tranlucent "Gem Series" bodies which proved very popular. Except that sunlight streaming through the clear body would set off the agitator even when it wasn't needed. VL's quick fix was to spray the insides of the necks with black spray paint.
When Brass Eagle bought out VL, for some unfathomable reason they dropped the black spray paint, which led to massive numbers of complaints about agitators activating, sometimes even indoors under stadium-type lighting. About the same time, BE switched to a cheaper plastic, which led to even more complaints about cracked feed necks or shattered screw holes.
So BE first put a band-aid on the light sensitivity in what they called the "Sun Board". This modulated the IR eye output and told the detector to only look for something in that frequency. It worked, but the "sense time"- time between it detecting a gap in the stack and turning the agitator on- was excessively long. I heard upwards of half a second. And at 10 bps, that's five shots' gap.
Finally, they redesigned the board, now called the X-Board, and have introduced highly durable polycarbonate (Lexan) shells. And roughly in this ballpark, the Ricochet, Halo and Mach 404 loaders have come out and gone through their own upgrade cycles.